Dual cylinder feeder for course granular material

ABSTRACT

A carriage reciprocates longitudinally across the lower ends of three upwardly extending passages, namely, a central outlet passage into which the granular material is to be fed, a first supply passage on the left side of the outlet passage and a second supply passage on the right side of the outlet passage. Mounted on the carriage are two parallel upright feed cylinders equipped with hydraulically actuated feed pistons with the two pistons operating 180* out of phase. At one of the two limit positions of the carriage, the right feed cylinder registers with the central outlet passage and the corresponding feed piston forces granular material upward from the cylinder into the outlet passage. At the same time the left feed cylinder registers with the left supply passage to receive a new charge of the granular material. At the second limit position of the carriage, the left feed cylinder registers with the central outlet passage to deliver material thereto and the right feed cylinder registers with the right supply passage to receive a new charge of the granular material.

United States Patent [191 Day [ Sept. 30, 1975 1 DUAL CYLINDER FEEDER FOR COURSE GRANULAR MATERIAL [76] Inventor: Donald F. Day, 9213 Tamarind,

Fontana, Calif. 92335 221 Filed: Oct. 15,1973

211 Appl. No.: 406,568

-[52] US. Cl. 222/135; 222/145; 417/516;

417/900 [51] Int. Cl. B67D 5/52; F04B 7/04 [58] Field of Search 214/17 C, 23; 222/134,

[56] References Cited UNITED STATES PATENTS 2.796.032 6/1957 Ballert 417/900 X 2,875,137 2/1956 Lieffers et al 202/93 X 3,663,129 5/1972 Antosh 417/516 3,667,869 6/1972 Schlecht 417/533 X Primary E.\amilzerRobert B. Reeves Assistant E \-aminerFrancis J. Bartuska 5 7 ABSTRACT A carriage reciprocates longitudinally across the lower ends of three upwardly extending passages, namely, a central outlet passage into which the granular material is to be fed, a first supply passage on the left side of the outlet passage and a second supply passage on the right side of the outlet passage. Mounted on the carriage are two parallel upright feed cylinders equipped with hydraulically actuated feed pistons with the two pistons operating 180 out of phase. At one of the two limit positions of the carriage, the right feed cylinder registers with the central outlet passage and the corresponding feed piston forces granular material upward from the cylinder into the outlet passage, At the same time the left feed cylinder registers with the left supply passage to receive a new charge of the granular material. At the second limit position of the carriage, the left feed cylinder registers with the central outlet passage to deliver material thereto and the right feed cylinder registers with the right supply passage to receive a new charge of the granular material.

US. Patent Sept. 30,1975 Sheet 2 of3 3,98,865

*ll Hil USE Patent Sept. 30,1975 Sheet 3 Of3 3,908,865

BACKGROUND OF THE INVENTION The invention're lates to feeding apparatus for pump ing coarse granular material from a bulk supply into a processing zone. Such an apparatus may be used, for example, to feed crushed oil shale into a retort for extraction of hydrocarbons therefrom OrQas another ex'-' ample, such an apparatus may be used to feed coal into a coking retort. i

More particularly described, the disclosure relates to a feeder of the type in which a feed cylinder equipped with a feed piston first registers with a supply passage to receive a charge of the'granular material from a bulk supply and then registers with an outlet passage leading to the processing zone to permit the feed piston to force the charge of granular material from the feed cyl inder into the outlet passage.

An apparatus of this cylinder-and-piston type is dis closed, for example, in the Lieffers et al. US. Pat. NO. 2,875,137 and in the I-Iemmingefet al: US. Pat. No. 3,162,538. In each of these disclosures the feed cylinder is pivoted at its lower end to swing between'an inclined position and a vertical position. At the inclined position the feed cylinder with its feed piston retracted registers with a supply passage to receive a charge of granular material from bulk storage. At the second or vertical position the feed cylinder registers with a'vertical outlet passage that lcads to the processing zone and the feed piston advances to force'the content of the feed cylinder upward into the outlet passagel Since each discharge operation is followed by a refill operation of equal time duration the feeding action is intermittent. In fact the feeding operation occurs over less than 50% of the operating time of the apparatus. 7

SUMMARY OF THE INVENTION tions with the two feed cylinders positioned parallel on the carriage and with the upper ends of the two feed cylinders adjacent the horizontal pathlAbove the path of reciprocation of the carriage are three upwardly extending passages, namely, a central outlet passage which leads to the processing zone, a first supply passage to the left of the outlet passage and a second supply passage to the right of the outlet passage. I

At one of the two limit positions of the carriage, the right feed cylinder registers with the outlet passage and the left feed cylinder registers with the left supply passage to receive a charge of the granular material from bulk supply. The feed pistons in the two cylinders'operate at nearly 180 out of phase so that while the feed piston in the right cylinder is advancing to force its load into the outlet passage the other feed piston in the'left feed cylinder is retracting to admit granular material from the bulk supply. At the alternate position of the carriage, the left feed cylinder registers with the central outlet'to deliver material thereto and the right feed cyl-- inder registers with the right supply passage to receive a new charge of material. Thus, material is displaced into the outlet passage at each of the two 'alternate positions of the carriage with no loss of time involved in the replenishing of th'e'feedcylinde'rs.

The features and advantages of the invention may be understood from the following description together with theaccompanying drawings.

1 BRIEF. DESCRIPTION OF THE DRAWINGS In' the drawings, which are to regarded as merely illustrative i I FIG. 1 is a fragmentary sectional view of the feeder apparatus with the carriage at its left limit position;

FIG. 2 is'a horizontal section along the line 22 of FIG. 1 which is approximately in'th'e plane of the path of reciprocation of the carriage;

FIG. 3 is a fragmentary view similar to FIG. 1 showing the carriage at its right limitposition with the left feed piston ready to force granular material into the upright outlet passage;

FIG. 4 is a view similar to FIG. 3 showing the left feed piston fully advanced and the right feed piston fully retracted; v FIG. 5 is a fragmentary vertical section along the line 5 -5'of FIG. 4;

FIG. 6 is a diagrammatic view showing two four-way valves that are employed in the apparatus and showing 'in dotted lines the circuitry for controlling the two fourway valves; I,

FIG. 7 is a fragmentary diagrammatic view showing how two manually Operated four-way valves may be substitutedfor the automatically controlled four-'way valves;

FIG. 8 is a diagrammatic plan view showing how a rotary carriage may'be substituted for a linearly reciproeating carriage; and i v FIG. 9 is a fragmentary viewjsimilar to FIG. 8 showing the rotary carriage at an'alternate position.

DESCRIPTION OF THE SELECTED EMBODIMENT OF THE INVENTION Referring to FIGS. 1 and 5 of the drawingsthe fixed support structureiof'the apparatus includes a horizontal rectangular I-beam frame 10 and a wide channel bar 12 with upwardly extending side flanges welded to the un-' derside of the I-beam frame. As shown in FIGS. 2 and 5' the fixed ch'annel bar 12 is relatively wide and has a "row of three equally spaced circular openings 14, 15 and 16. As shown in FIG. 1 the fixed channel bar 12 supports a central upwardly extending outlet passage 18 that feeds a retort l9 and'the central opening 15 of the fixed channel bar 12 is the entrance port to this passage. The fixed channel bar'12 also supports an inclined left supply passage 20 in communication with the left opening 14 of the fixed channel bar and further supports an inclined right supply passage 22 which terminates at the right opening 16 of the fixed channel bar. I i

- A reciprocativ'e carriage 24 carries two parallel upright feed cylinders comprising a right feed cylinder 25 and a left feed cylirider 26. The carriage 24 is in the form of'a second relatively wide channel bar with depending side" flanges and is positioned immediately below the fixed channelfbar 12in back-to-back relationship thereto.' The carriage or movable channel 24 travels on four rollers 28 that are rotatably mounted on corresponding fixed brackets 29 that depend from the fixed channel bar 12.

The upper end of the right feed cylinder 25 is welded to the rim of a circular opening 30 of the carriage 24 and in like manner the left feed cylinder 26 is welded at its upper end to the rim of a second circular opening 31. The axes of the two feed cylinders 25 and 26 are separated by a given distance which is the same distance that separates the axis of the opening 14 in the fixed channel member 12 from the axis of the opening 15. The same distance separates the axis of the opening 15 from the axis of the opening 16. The left end of the carriage 24 is blank to form a gate 32 to cooperate with the left supply passage and in like manner the right end of the carriage is blank to form a gate 33 to cooperate with the right supply passage 22.

At the left limit position of the carriage 24 shown in FIG. 1 the upper end of the right feed cylinder 25 registers with the upright outlet passage 18, the left feed cylinder 26 registers with the left supply passage 20 and the right gate 33 cuts off the right supply passage 22. On the other hand, at the right limit position of the carriage 24 shown in FIG. 3 the upper end of the right feed cylinder 25 registers with the exit of the right supply passage 22, the upper end of the left feed cylinder 26 registers with the entrance to the upright outlet passage 18 and the left gate 32 cuts off the left supply passage 20. The cross-sectional area of each of the three passages 18, 20 and 22 is greater than the cross-sectional area of the two feed cylinders 25 and 26 to facilitate upward displacement of the granular material into the outlet passage 18 and to facilitate downward flow of material from each of the supply passages 20 and 22 to replenish the feed cylinders.

Any suitable arrangement may be employed to reciprocate the carriage 24 between its two limit positions. In the construction shown in the drawings, a doubleacting hydraulic cylinder 34 is supported at its outer end by a pivot 35 on a fixed bracket 36 and a piston rod 38 connected to a piston 40 in the hydraulic cylinder is connected by a pivot 42 to a downwardly extending bracket 44 of the carriage 24. The double-acting hydraulic cylinder 34 is controlled by a first four-way valve 45 which is connected to opposite ends of the hydraulic cylinder by conduits 46 and 48 and is also connected to a high pressure conduit 50 and a low pressure return conduit 52.

A feed piston 54 in the right feed cylinder 25 is connected by a connecting rod 55 to a power piston 56 in a lower double-acting hydraulic power cylinder 58 and, in like manner, a feed piston 60 in the left feed cylinder 26 is connected by a connecting rod 61 to a power piston 62 in a corresponding lower double-acting power cylinder 63. The two double-acting lower power cylinders 58 and 63 are mounted by corresponding lower pivots 64 on supporting framework 65 that depends from and is welded to the two cylinders 25 and 26 on the carriage 24.

The two double-acting power cylinders 58 and 63 respectively are both controlled by a second four-way valve 66 that is connected to a high pressure supply conduit 68 and a low pressure return line 70. A conduit 72 from one side of the four-way valve 66 has a branch 74 to the upper end of the power cylinder 58 and has a branch 75 to the lower end of the power cylinder 63. A second conduit 76 from the other side of the fourway valve 66 has a branch 78 to the lower end of the power cylinder 63 and a branch 80 to the upper end of the power cylinder 66.

By virtue of this arrangement initiation'of the actuation of the two feed pistons 54 and 60 in opposite directions occurs simultaneously, but since there is substantially greater resistance to upward movement of the two feed pistons 54 and 60 than to downward movement of the pistons the upward movement of each feed piston lags behind the downward movement of the other feed piston. Thus the upward stroke of the other piston is completed before the downward stroke of the other piston is completed.

in the presently preferred practice of the invention, the two four-way valves the first and second 45 and 66 are actuated automatically to carry out repeated cycles of operation of the apparatus. For this purpose a normally open terminal switch A is positioned on the support structure of the apparatus in the path of reciprocation of the carriage 24 to be closed by movement of the carriage to its left limit position and, in like manner, a normally open terminal switch C is positioned opposite the other end of the carriage to be closed by the carriage as the carriage reaches its right limit position. A normally open terminal switch B having an operating arm 82 is positioned to be closed by a collar 84 on the piston rod 55 when the feed piston 54 in the right feed cylinder 25 reaches its upper limit position. In like manner, a normally open terminal switch D having a similar operating arm 82 is positioned to be closed by a collar 85 on the piston rod 61 when the feed piston 60 in the left feed cylinder 26 reaches its upper limit position.

As shown diagramatically in FIG. 6, each of the two four-way valves 45 and 66 is a two position-four connection solenoid-actuated directional valve. The electrical circuit for the two four-way valves 45 and 66 is indicated by dotted lines in FIG. 5. The control circuit includes a master switch 86 which may be closed for automatic operation of the apparatus. Energization of the upper solenoid 88 of the second four-way valve 66 is controlled by the previously mentioned normally open terminal switch A; energization of the right solenoid 90 of the first four-way valve 45 is controlled by the normally open terminal switch B; energization of the lower solenoid 92 of the second four-way valve 66 is controlled by the normally open terminal switch C; and energization of the left solenoid 94 of the first fourway valve 45 is controlled by the normally open terminal switch D.

It is apparent that when the carriage 24 reaches its left limit position shown in FIG. 1, the normally open terminal switch A is closed to energize the upper solenoid 88 of the second four-way valve 66 to cause actuation of the second four-way valve in one respect to cause the piston 54 in the right feed cylinder 25 to rise to force a charge of the granular material upward into the outlet passage 18 and to cause simultaneous faster downward retraction of the feed piston 60 in the left feed cylinder 26 to permit a new charge of the granular material to gravitate into the left feed cylinder from the left supply passage 20.

When the feed piston 54 in the right feed cylinder 25 reaches its upper limit position as shown in FIG. 1, the collar 84 on the piston rod 55 closesthe normally open terminal switch B and thereby energizes the right solenoid 90 of the first four-way valve 45 to cause the carriage 24 to shift to its right limit position that is shown in FIG. 3.

When the carriage 24 reaches its right limit position it closes the normally open terminal switch C to energize the lower solenoid 92 of the second four-way valve 66 and thereby cause the feed piston 60 in the left feed cylinder 26 to move upward and at the same time cause the feed piston 54 in the right feed cylinder 25 to retract at a faster rate. FIG. 4 shows the left feed piston 60 fully extended to displace granular material into the outlet passage 18 and shows the right feed piston 54 fully retracted to permit the right feed cylinder 25 to be replenished from the right supply passage 22.

The delayed arrival of the left feed piston 60 at its upper limit position shown in FIG. 4 causes the collar 85 on the piston rod 61 to close the normally open terminal switch D and thereby energize the left solenoid 94 of the first four-way valve 45 to cause the carriage 24 to return to its initial position shown in FIG. 1.

FIG. 7 shows how a manual four-way valve 95 operated by a handle 96 may be substituted for the four-way valve 45 and how a manual four-way valve 98 controlled by a handle 100 may be substituted for the fourway valve 66. An operator repeatedly manipulates the valve handles 96 and 100 to carry out repeated cycles of operation of the apparatus.

FIGS. 8 and 9 show diagramatically how a carriage in the form of a carousel 102 equipped with three pairs of parallel cylinders (not shown) may be oscillated through a small angle about a pivot 103 to feed material into three retorts 104 simultaneously. The carousel 102 is oscillated by a hydraulic cylinder 105 that is pivotally mounted on a fixed bracket 106 with the piston rod 107 of the hydraulic cylinder pivotally connected to a spoke 108 of the carousel. The carousel 102 is stabilized by equally spaced rollers 109. Immediately above the carousel 102 is a stationary ring-shaped plate 110 which has the same purpose as the fixed channel bar 12 in the first embodiment in that it carries the three retorts 104 and the associated pairs of supply passages. At the position of the carousel 102 indicated in FIG. 8, the right feed cylinders of the pairs of parallel feed cylinders are in positions to discharge their contents into the corresponding retorts 104; the left feed cylinders of the pairs are in positions to be replenished from corresponding supply passages; and the carousel cuts off the idle supply passages. At the alternate position of the carousel 102 that is indicated in FIG. 9 the left feed cylinders of the pairs of feed cylinders register with the retorts 104; the right feed cylinders of the pairs register with corresponding supply passages that are associated with the retorts; and the carousel cuts off the supply passages that are not in use.

My description in specific detail of the invention will suggest various changes, substitutions and other departures from my disclosure within the spirit and scope of the appended claims.

I claim:

I. In an apparatus for feeding course granular material, for example crushed oil shale upward to a given region, the combination of: l

a carriage movable along a path below said region between a first position of the carriage and a second position of the carriage;

a fixed outlet passage extending'upward from said path to said region;

first supply passage to supply said material, said first supply passage being located on said path on one side of said outlet passage and extending downward to said path;

a second supply passage to supply said material, said a second cylinder on the carriage of substantially the same outside diameter as the first cylinder and spaced from the first cylinder along said path, said second cylinder being below said path and extending upward to the path;

a second piston reciprocative in said second cylinder; a first gate on the carriage extending along said path in one direction away from the two cylinders; second gate on the carriage extending along said path in the opposite direction away from the two cylinders,

the outlet passage and the two supply passages being so located along the path and the two cylinders and the two gates being so located on the carriage that at the first position of the carriage the second cylinder registers with the outlet passage, the first cylinder registers with the first supply passage to receive material gravitationally therefrom, and one of the two gates closes the second supply passage and at the second position of the carriage the first cylinder registers with the outlet passage, the second cylinder registers with the second supply passage to receive material gravitationally therefrom, and the other of the two gates closes the first supply passage;

a first double-acting fluid-actuated power cylinder to two double-acting fluid-actuated power cylinders to operate the two pistons respectively;

a second four-way valve connected oppositely to said two double-acting fluid-actuated power cylinders to control both of the two power cylinders, whereby the opposite movements of the two pistons are initiated simultaneously, but the greater load on the upwardly moving piston causes completion of the upward movement of the piston to lag behind the completion of the downward movement of the other piston;

first normally open terminal switch to close in response to completion of the upward movement of one of the two pistons to operate the first four-way valve in one of its two respects to shift the carriage to one of its two positions;

second normally open terminal switch to close in response to arrival of the carriage at said one of its two positions to operate the second four-way valve in one of its two opposite respects;

third normally open terminal switch responsive to completion of the upward movement of the other of the two pistons to operate the first four-way valve in its opposite respect to shift the carriage to the other of its two positions; and

a fourth normally open terminal switch responsive to arrival of the carriage at said other of its two positions to operate the second four-way valve in its opposite respect. 

1. In an apparatus for feeding course granular material, for example crushed oil shale upward to a given region, the combination of: a carriage movable along a path below said region between a first position of the carriage and a second position of the carriage; a fixed outlet passage extending upward from said path to said region; a first supply passage to supply said material, said first supply passage being located on said path on one side of said outlet passage and extending downward to said path; a second supply passage to supply said material, said second supply passage being located on said path on the other side of said outlet passage and extending downward to said path; a first cylinder on the carriage below said path and extending upward to the path; a first piston reciprocative in said first cylinder; a second cylinder on the carriage of substantially the same outside diameter as the first cylinder and spaced from the first cylinder along said path, said second cylinder being below said path and extending upward to the path; a second piston reciprocative in said second cylinder; a first gate on the carriage extending along said path in one direction away from the two cylinders; a second gate on the carriage extending along said path in the opposite direction away from the two cylinders, the outlet passage and the two supply passages being so located along the path and the two cylinders and the two gates being so located on the carriage that at the first position of the carriage the second cylinder registers with the outlet passage, the first cylinder registers with the first supply passage to receive material gravitationally therefrom, and one of the two gates closes the second supply passage and at the second position of the carriage the first cylinder registers with the outlet passage, the second cylinder registers with the second supply passage to receive material gravitationally therefrom, and the other of the two gates closes the first supply passage; a first double-acting fluid-actuated power cylinder to shift the carriage to its two opposite positions alternately; a first four-way valve to control the first double-acting fluidactuated power cylinder; two double-acting fluid-actuated power cylinders to operate the two pistons respectively; a second four-way valve connected oppositely to said two doubleacting fluid-actuated power cylinders to control both of the two power cylinders, whereby the opposite movements of the two pistons are initiated simultaneously, but the greater load on the upwardly moving piston causes completion of the upward movement of the piston to lag behind the completion of the downward movement of the other piston; a first normally open terminal switch to close in response to completion of the upward movement of one of the two pistons to operate the first four-way valve in one of its two respects to shift the carriage to one of its two positions; a second normally open terminal switch to close in response to arrival of the carriage at said one of its two positions to operate the second four-way valve in one of its two opposite respects; a third normally open terminal switch responsive to completion of the upward movement of the other of the two pistons to operate the first four-way valve in its opposite respect to shift the carriage to the other of its two positions; and a fourth normally open terminal switch responsive to arrival of the carriage at said other of its two positions to operate the second four-way valve in its opposite respect. 